Power Apps – Understanding ‘Variables’

January 26, 2020 Leave a comment

If you are a ‘Power Apps’ beginner and wonder how to declare and use variables like the way you do in any of your favorite programming language (C#, Java, PHP, etc..) this article is for you.

Before we jump in to ‘Power Apps’ Variables, lets first understand following things:

  • ‘Power Apps’ is different and works more like Excel.
  • Power Apps and Excel both automatically recalculate formulas as the input data changes, without the need of Variables.
  • In below screen,
    • Sum of A and B is being calculated and set to the Label just by summing up the Text values directly like a formula.
    • If either A or B value changes, Label will recalculate the value.

PA_Var1

Why we need variables in ‘Power Apps’?

  • In general, its recommended to avoid using variables in Power Apps.
  • But sometimes only a variable can enable the experience you want.
  • To understand this, lets tweak the previous screen by adding a Button and Sum up the values on button click.

PA_Var2

  • Here we can’t use formulas (i.e., Like screen 1) to calculate the Sum because its value depends on button Click.
  • We require a variable to hold the Sum before its set to the Variable to display.

Types of Variables:

Power Apps has three types of variables:

PA_Var3

Global Variable:

  • You set the value of the global variable with the Set function.
    • Set( Var_Name, 0 ) sets the global variable to a value of 0.
  • Global variables can hold any value, including strings, numbers, records, and tables
  • In my example, on ‘OnSelect’ of ‘Calculate’ button, using ‘Set’ function, I am setting Sum of txt1.Text and txt2.Text to a Global variable ‘globalVar‘.

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  • And setting the ‘Text’ of ‘Label’ to Global variable ‘globalVar‘.

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  •  Global variable scope is ‘App’ level, can be references from anywhere in the app. Which means, I can read the ‘globalVar‘ from a different screen (i.e., Screen2).

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Context Variable:

You implicitly establish and set context variables by using the UpdateContext or Navigate function.

UpdateContext:

  • UpdateContext( { Var_Name: 0} ) sets the context variable to a value of 0.
  • Context variables can hold any value, including strings, numbers, records, and tables
  • In my example, on ‘OnSelect’ of ‘Calculate’ button, using ‘UpdateContext’ function, I am setting Sum of txt1.Text and txt2.Text to Context variable ‘ctxVar‘.

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  • And setting the ‘Text’ of ‘Label’ to Context variable ‘ctxVar‘.

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  • ‘OnSelect’ of ‘Clear Context Variable’ button, I am setting ‘ctxVar‘ to 0.

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  • Context variable set using ‘UpdateContext’ function’s scope is ‘Screen’ level, can only be references with in the screen.

Navigate:

  • You can also set a context variable when you use the Navigate function to show a screen.
  • In the example below, lets add a new button ‘Navigate to Screen2’ and on ‘OnSelect’, navigate to ‘Screen2’ by passing ‘ctxvar‘ as argument.
    • Navigate(Screen2,ScreenTransition.Fade,{ctxvar:txt1.Text+txt2.Text})

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  • On ‘Screen2’ set the Label’s text to ‘ctxvar’.

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  • Run the application, click on ‘Navigate to Screen2’

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  • On the ‘Screen2’ we get ‘ctxvar’ value displayed in label.

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  • Important thing to notice is, Except for Navigate, context variables are limited to the context of a single screen, which is where they get their name. You can’t use or set them outside of this context.

Use Collection:

  • Collection holds a table that is easy to modify.
  • Create and set collections by using the ClearCollect function.
    • You can use the Collect function instead, but it will effectively require another variable instead of replacing the old one.
  • In my example, on ‘OnSelect’ of ‘Add to Collection’ button, collect the ‘txt1.Text’ values to a collection ‘collSum‘ using Collect(collSum,txt1.Text)

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  • We clear the Collection ‘collSum‘ using Clear(collSum) function.

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  • To display the ‘collSum’ values, add a ‘DataTable’ control and set ‘Data source’ to ‘collSum’.

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  • Run the application and keep adding the values. You should see collection values in a table as below.

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Notes:

  • You can see the Variables and Collection on the File menu of your App.

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  • If you give a context variable the same name as a global variable or a collection, the context variable takes precedence. However, you can still reference the global variable or collection if you use the disambiguation operator @[Var_Name].
  • All variables are held in memory while the app runs. After the app closes, the values that the variables held are lost.
  • When the user opens the app, all variables have an initial value of blank.

🙂

 

 

 

 

 

Categories: CRM

D365 – Shifting from Dynamics Workflow to Power Automate flow

December 11, 2019 Leave a comment

First things first, Microsoft Flow is now Power Automate.

If you are either a dynamics developer or administrator, off late you might have noticed a flashing banner while creating new Process from Dynamics instance.

Flow_Scope_4

From the banner, its clear that Microsoft recommends ‘Power automate flows’ over conventional ‘Process’.

In this article, I am going to cover basics of following items, which helps you in decision making to some extent.

Lets get in to the details.

CDS connector vs Dynamics connector:

When you are creating a flow, you need to choose b/w CDS and Dynamics connector.

The key differentiation when switching from Dynamics ‘Process’ to ‘Flow’ is,

  • With CDS connector you can set ‘Scope’ and ‘Filter Attributes’ but not with Dynamics connector.

Lets understand this with an example.

Create a flow with CDS connector:

  • Connect to your Power automate portal
  • Click on ‘+ Create’ tab and choose ‘Automated flow’

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  • In the new window, choose the ‘Common Data Service’ connector.

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  • Under the ‘Triggers’, select ‘When a record is updated’ trigger.

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  • If you notice, under ‘When a record is updated’, there are ‘Scope’ and ‘Attribute Filter’ options.
    • Scope : Scope decides the affected records up on flow execution. Get more details here.
    • Flow_Scope_1
    • Attribute Filter: If no filtering attributes are set flow will execute on every field updates. Add attribute filters to minimize flow execution, only on specified field updates.
    • Flow_Scope_3
  • Now add an action from the ‘Actions’ list. I’ve added a ‘Create a new record’ action.

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Create a flow with Dynamics 365 connector:

  • Connect to your Power automate portal
  • Click on ‘+ Create’ tab and choose ‘Automated flow’
  • In the new window, choose the ‘Dynamics 365’ connector.

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  • Under the ‘Triggers’, select ‘When a record is updated’ trigger.

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  • This time, under ‘When a record is updated’ there are NO ‘Scope’ and ‘Attribute Filter’ options.

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  • Which means, the flow will trigger on all field updates and there is no provision of ‘Attribute Filter’ in Dynamics 365 Connector.

Automated flow vs Instant flow (i.e., On-demand process):

One of the common questions from Admins is, how can they create an ‘On-demand’ power automate flow similar to conventional ‘On-demand’ workflow. The answer is Instant flow.

Lets see how to create a simple on-demand flow and run.

Create an Instant Flow:

  • Connect to your Power automate portal
  • Click on ‘+ Create’ tab and choose ‘Instant flow’
    • Note: You can also create ‘Instant flow’ from Dynamics application.
    • Go to the entity, from ‘Flow’ menu, click on ‘Create a flow’.

Flow_Scope_18

  • In the new window, choose the ‘Common Data Service’ connector.
  • Under the ‘Triggers’, select ‘When a record is selected’ trigger.
  • Select the ‘Environment’ and ‘Entity Name’
    • Environment: If you want your flow to always trigger based on an event in a specific environment, select that environment or Choose (Default), which will always use the database within the environment in which Power Automate runs.
  • Now add an action from the ‘Actions’ list. I’ve added a ‘Create a new record’ action.

Flow_Scope_8

  • In above screen, I am setting ‘Transaction Audit’ entities ‘Name’ field with concatenating ‘Transactions’ entities ‘Name’ and current date (i.e., utcNow()).
    • Use ‘Dynamic content’ window, to refer the values from Previous step.

Trigger Instant Flow:

  • Connect to Dynamics instance and open the record for which you have flow registered. In my case, my flow registered on ‘Transaction’ Entity.
  • From the ‘Flow’ menu, select your flow.

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  • Click on ‘Run flow’

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  • Make sure you got the success screen as below.

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  • Now check whether the Action executed. In my example, I am creating a child record (i.e., Transaction Audit)

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Formatting Dates:

If you would have noticed the previous screen, the ‘Name’ field of the ‘Transaction Audit’ was set to UTC date format.

To format the date to your choice, use formatDateTime function in your flow’s ‘Expression’.

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Save and run the flow, you should see the formatted date as below.

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Notes:

  • One more edge CDS connector over Dynamics connector is in terms of execution speed. More details

🙂

 

 

 

 

 

 

 

 

Obsolete Secure Communications Protocol Supported – InfoSec – Fix

December 9, 2019 Leave a comment

Last week our web application (i.e., ADX portal website) underwent Penetration testing (Also called ‘Ethical hacking’) and we got following recommendation:

Disable all affected protocols identified above. If possible, implement TLSv1.3, or TLSv1.2 otherwise.

Reason:

  • In our application’s web server (IIS), TLSv1.0 and TLSv1.1 communication protocols were enabled.
  • TLSv1.0 and TLSv1.1 were deprecated in major browsers as of Q1 2019 and will be disabled completely in early 2020.

Fix:

  • We’ve used IIS Crypto tool to disable TLSv1.0 and TLSv1.1 protocols.
  • IIS Crypto is a free tool that gives administrators the ability to enable or disable protocols, ciphers, hashes and key exchange algorithms on Windows Servers.
  • Download the IIS Crypto GUI tool in your windows server where your application is hosted.

IIS Crypto_1

  • Open the tool and un-check TLSv1.0 and TLSv1.1 options.

IIS Crypto

  • You must restart the server for changes to take effect.

🙂

 

Categories: ADX, Misc Tags: , ,

Dynamics workflow – Unable to set Email ‘Regarding’ field

December 3, 2019 Leave a comment

Other day, while working on a straight forward ‘Send Email’ using a ‘Workflow’, I could not set the ‘Regarding’ field on ‘Email’ form.

Scenario:

  • Create a new custom entity ‘Transaction’.
  • Send an Email when a new ‘Transaction’ record gets created.

So, I created a new workflow on ‘Transaction’ entity and added ‘Send Email’ step.

SendMail_0.PNG

On the ‘Email’ configuration screen, all I could see was a blank ‘Look for:’ field.

SendMail_1

Reason & Fix:

  • ‘Activities’ option was not enabled on the ‘Transaction’ entity.

SendMail_2

  • Enable ‘Activities’ and publish.
  • Go to the workflow and I got the Entity Reference in ‘Look for:’ field.

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Its one of those days where we struggle for trivial problems 🙂

 

Categories: CRM Tags: ,

BotDetect Captcha – 404 error – images are not loading

November 29, 2019 Leave a comment

Recently we leveraged BotDetect libraries in our Aspx MVC application to generate CAPTCHA.

After configured all the steps, CAPTCHA images were not showing up on web page.

CAPTCHA_1

Using browsers F12 option, we could notice there were 404 (i.e., Not Found) error codes.

CAPTCHA_2

Fix:

  • Issue in our case was all the BotDetect requests getting routed, which should not be.
  • Add below statement in your project’s ‘RouteConfig.cs’ file, which prevents BotDetect requests routing.

// BotDetect requests must not be routed
routes.IgnoreRoute(“{*botdetect}”,  new { botdetect = @”(.*)BotDetectCaptcha\.ashx” });

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  • Rebuild the project and run and you should get the CAPTCHA code.

CAPTCHA_4

Refer article for the steps to configure CAPTCHA in MVC application.

🙂

Categories: ADX Tags: , ,

ADX Portal – Prevent unauthorized access of custom pages

November 26, 2019 Leave a comment

For one of our requirements, we built a custom .aspx page and placed under ‘Areas’ folder of OOB ADX website’s ‘MasterPortal’ project.

ADX_Prevent_UnAuthAccess

Issue:

  • The .aspx page was accessible without signing in to the portal by using the following URL convention
    • https://base_portal_url/Areas/folderName/Pages/filename.aspx

Fix:

  • On Page_Load of the aspx page, check whether the request is from authenticated user or not.
  • If unauthenticated request, set 401 error code (i.e., Unauthorized error) to the Response object and redirect to portals ‘SignIn’ page.
  • Below is the code snippet need to be placed in Aspx page’s ‘Page_Load’ event, which redirects unauthenticated requests to Portal’s ‘SignIn’ page.

protected void Page_Load(object sender, EventArgs e)
{
if (!Request.IsAuthenticated)
{
Response.StatusCode = 401;
Response.End();
}
}

🙂

Categories: ADX Tags: , ,

ADX/Dynamics portal – Setting up password policies

November 21, 2019 Leave a comment

If you want to imply password policy (i.e., Certain length, must have a digit, etc…) during the portal registrations, following entries need to be added to ‘Site Settings’ entity.

ADX_PasswordPolicy_1.PNG

Name Value
Authentication/UserManager/PasswordValidator/AlphanumericUserNames TRUE
Authentication/UserManager/PasswordValidator/RequireDigit TRUE
Authentication/UserManager/PasswordValidator/RequiredLength 9
Authentication/UserManager/PasswordValidator/RequireLowercase TRUE
Authentication/UserManager/PasswordValidator/RequireNonLetterOrDigit TRUE
Authentication/UserManager/PasswordValidator/RequireUppercase TRUE

If the password does not meet any of the configured setting values, you gonna get OOB validation error as follows:

ADX_PasswordPolicy

For more ‘Authentication’ related settings, refer the article

Refer this article for portals client scripting.

🙂